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51.
Summary

DNA-based RAPD (Random Amplification of Polymorphic DNA) markers have been used extensively to study genetic relationships in a number of fruit crops. A wide genetic diversity exists in the mango fruit in India. Present day commercial cultivars originated mainly from this subcontinent. In this study, 18 commercial mango cultivars, traditionally grown in western, southern, northern and eastern parts of India, were selected to assess genetic relatedness. Total genomic DNA was extracted and subjected to RAPD analysis using 30 arbitrary 10-mer primers. Of these, 27 primers amplified mango genomic DNA. None of these primers produced unique band pattern for each cultivar. RAPD data were used to calculate a squared Euclidean distance matrix, and based on this cluster analysis was done using a minimum variance algorithm. Cluster analysis clearly showed two groups—the first consisting of western, northern and eastern mango cultivars and the second group consisting of southern cultivars. From the analysis of results, it appears the majority of mango cultivars originated from a local mango genepool and were domesticated later.  相似文献   
52.
Summary

Randomly amplified polymorphic DNA (RAPD) markers were used to estimate genetic diversity among 24 cultivars of short-day onions. Total genomic DNA was extracted and subjected to RAPD analysis using 90 arbitrary 10-mer primers. Of these, 15 primers were selected which yielded 137 bands, 91.24% of which were polymorphic. None of the primers produced a unique banding pattern for each cultivar. RAPD data were used to calculate a Squared-Euclidian Distance matrix which revealed a minimum genetic distance between cultivars ‘AFLR-722’ and ‘PBR-140’, and a maximum genetic distance between cultivars ‘PBR-139’ and ‘A.Kalyan’, and ‘MS-48’ and ‘A.Kalyan’. Based on the distance matrix, cluster analysis was done using a minimum variance algorithm.The dendrogram thus generated, based on Ward’s method, grouped the 24 onion cultivars into two major clusters. The first cluster consisted of cultivars from the northern region, and the second of cultivars from the southern region of India. The present study shows that there is high diversity among the onion cultivars selected and indicates the potential of RAPD markers for identification and maintenance of onion germplasm for crop improvement purposes.  相似文献   
53.
Protease inhibitors play a protective role against pathogenic microorganisms and herbivorous insects. The two predominant protease inhibitors of soybean seeds are the Kunitz trypsin inhibitor (KTI) and Bowman-Birk protease inhibitor (BBI). In this study, we report that soybean seeds incubated in warm water release large amounts of proteins into the surrounding media. Two-dimensional gel electrophoresis analysis of the seed exudates resulted in the separation of 93 distinct protein spots out of which 90 spots were identified by LC-MS/MS. The basic 7S globulin and the BBI are the two predominant proteins found in the soybean seed exudates. In addition to 7S and 11S seed storage proteins, others known to protect the seeds against pathogens and pests including KTI, peroxidase, α-galactosidase, and endo-1.3-β-glucanase were also identified in the seed exudates. Soybean seed exudate obtained by incubating the seeds in warm water was also able to inhibit the growth of human breast cancer cell line MCF-7. Since soybean seeds release large amounts of enzymatically active BBI when immersed in warm water, our procedure could be exploited as a simplified alternative method for the preparation of BBI concentrate which is being used as a cancer chemoprotective agent.  相似文献   
54.

Aquaculture is growing post-haste in recent years particularly in the fish and shrimp production. The rapid growth of aquaculture and increasing demand for fish have led to a rapid development of the fish and shrimp industry, resulting in increased production of both fish and shrimps. As a result, there is a greater risk of disease outbreaks. Mass mortalities in aquaculture are primarily due to infectious diseases caused by bacteria, viruses, and fungi. Among them, viral diseases are the most devastating, causing huge loss in the production of both cultured fish and shellfishes. There are several effective methods of treatment for these disease outbreaks. This review focuses on various methods of controlling the viral pathogens using various treatment methods like use of medicinal plants and seaweed extracts, bioactive compounds from actinomycetes, vaccines, probiotic microbes, chemicals, nanoparticles, and green synthesis of nanoparticles.

  相似文献   
55.
Both 1-methylisopropyl 2-(2-hydroxyethyl)piperidine-1-carboxylate, (Picaridin((R))) and cyclohex-3-enyl 2-methylpiperidin-1-yl ketone (AI3-37220; 220) have two asymmetric centers, and the four diastereoisomers of each compound are known to have differing degrees of mosquito-repellent activity according to quantitative behavioral assays conducted at the United States Department of Agriculture. Computational chemistry was used to identify the structural and configurational basis for repellent activity. Molecular overlay of the optimized geometries of the lowest energy conformers of the diastereoisomers was investigated to elucidate the role of chiral centers in 220 and Picaridin. It was found that the presence of a chiral carbon alpha to the nitrogen with the S configuration in the piperidine ring is essential to the three-dimensional arrangement of the atoms of the pharmacophore for effective repellent activity.  相似文献   
56.
57.
The effects of acute and chronic exposures to a sublethal concentration (1.7 mg/liter) of oxydemeton-methyl (Metasystox) on the activities of branchial enzymes Na, K-ATPase, Mg-ATPase, alkaline phosphatase, acid phosphatase, aspartate aminotransferase, and alanine aminotransferase were determined. While chronic and acute treatments inhibited Na, K-ATPase and Mg-ATPase concentrations, an insignificant rise in the activities of alkaline and acid phosphatases was noticed in the acute treatment. However, both chronic exposures decreased the activities of these phosphatases. A progressive accumulation of AAT and AlAT, with a maximum occurring after 30 days, was recorded. The significance of the results are discussed.  相似文献   
58.
Present paper reports a method of preparing polymer composite electrolyte nanofiber mat using polyvinyl alcohol (PVA), ammonium thiocynate (NH4SCN) salt, and aluminium oxide (Al2O3) nano particles based on electrospinning technique. Two-stage process of preparation of nanofibers, namely, preparation of nano particles filled PVA electrolyte gel solution followed by its electrospinning has been used. The so obtained nanofibers have been characterized by XRD, DSC, SEM, and Conductivity measurements. XRD patterns affirm the formation of nanocomposite while SEM pictures reveal formation of fibers on a nano scale format (300–800 nm). Fibers of the electrolytes are seen to be thermally stable. Ionic conductivity of electrolyte fiber is seen to improve in the presence of nano filler at room temperature with a maximum at 5.31×10−3 Scm−1 for 4 wt% filler concentration, which is comparable to that for corresponding dried gel electrolyte films.  相似文献   
59.
The present study aims to understand the influence of freeze-dried shrimp (Penaeus monodon) meat (SM) at different levels (2.5, 5, and 10%; w/w) in pasta processing. The rheological characteristics studies of SM-wheat flour blends indicated that dough stability increased with the increased addition of SM in the blends, whereas farinograph water absorption and amylograph peak viscosity decreased. Cooking loss increased with increasing levels of SM in the pasta (7.3% in 10% SM pasta; 6.7% in control pasta). However, all pasta samples were in the acceptable range. Color analysis of the pasta sample indicated that the L values increased with increasing levels of pasta. The instrumental texture of cooked pasta indicated that 10% SM pasta was significantly (p < 0.05) firmer (1.84 N) than that of the control (1.35 N). Microstructure studies revealed that incorporation of SM in the pasta had a better protein network. Pasta with 5% SM had the highest mean score for all sensory attributes, with increased levels of essential nutrients, fatty acids such as eicosapentaenoic acid and docosahexaenoic acid, and amino acids such as lysine.  相似文献   
60.
The present work reports the preparation of Poly L-Lactide (PLLA) and Curcumin loaded Poly L-Lactide (CPLLA) nanofibers by electrospinning. A series of PLLA solution (12 wt %) and C-PLLA (12 wt % PLLA) solution containing Curcumin (0.5 wt % and 1 wt %)) were electrospun into nanofibers. SEM images showed the average diameter of PLLA and C-PLLA in the range of 50?C200 nm. The TEM images showed the dispersion of Curcumin on C-PLLA nanofibers. The XRD pattern indicated decreases of crystallinity with the increase in the amount of Curcumin. The characteristic peak of Curcumin was confirmed by FTIR. The TGA results showed the degradation of PLLA and C-PLLA close to 300 °C. The percentage porosity and the contact angle of PLLA were found to be 90.2 % and 115±3 ° with deionised water, respectively. The water uptake percentage was found to be 17.6 %. The percentage cumulative release of Curcumin at the end of 8th day for 0.5 and 1.0 wt % formulations was 81.4±1.3 and 86.7±1.7 % respectively. The in-vitro biological cytotoxicity studies were performed using C6 glioma cells and NIH 3T3 fibroblast by MTT assay and SEM analysis.  相似文献   
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